Key points are not available for this paper at this time.
Marian Sigman, Charlotte Neumann, Ake A. J. Jansen, Nimrod Bwibo, Cognitive Abilities of Kenyan Children in Relation to Nutrition, Family Characteristics, and Education, Child Development, Vol. 60, No. 6 (Dec., 1989), pp. 1463-1474
Sigman et al. (Fri,) studied this question.